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Full-Text Articles in Biology

Does Interest Equal Success? Evaluating Student Perceptions Of The Study Of Biology And Their Effects On Student Success In An Introductory Biology Course, Courtney Irene Barlow May 2018

Does Interest Equal Success? Evaluating Student Perceptions Of The Study Of Biology And Their Effects On Student Success In An Introductory Biology Course, Courtney Irene Barlow

Honors Theses

As instructors begin to devote more time to improving student perceptions of biology, the validity of these efforts should be determined. Do students possessing favorable views of biology regularly perform on a higher level than those with less favorable impressions, or would class time be better spent without exercises intended to increase student interest? The goal of this project was to address the research questions “How do students view the study of biology?”, “How do student perceptions of the subject area affect their performance in an Introductory Biology course?”, and “How does a student’s chosen area of study affect their …


Salve Regina Arboretum Ten Year Plan To Reach Level Iii Accreditation, Jameson Chace, Helen Papp, Allyson Gilbert, Madeline Lark, Kyle Mcguire, Krysta Tsangarides, Madisen Archibald, Meghan Beals, Mackenzie Begley, Meagan Clickner, Makayla B. Cormier, Erin H. Donovan, Paige Dostie, Luke A. Gagnon, Micaela Griffin, Dana Johnson, Kunsang C. Lama, Kyle A. Macleod, Shannon A. Miller, Megan Moschetti, Amanda Munoz, Jennifer O'Connell, Erin O'Neill, Emily A. Riley, Alejandro C. Rojas, Ryan T. Senecal, Delaney A. Smith, Nicholas J. Sousa, Karolyne N. Stimpson, Sabrina Vieira, Mckenzie R. Wood May 2018

Salve Regina Arboretum Ten Year Plan To Reach Level Iii Accreditation, Jameson Chace, Helen Papp, Allyson Gilbert, Madeline Lark, Kyle Mcguire, Krysta Tsangarides, Madisen Archibald, Meghan Beals, Mackenzie Begley, Meagan Clickner, Makayla B. Cormier, Erin H. Donovan, Paige Dostie, Luke A. Gagnon, Micaela Griffin, Dana Johnson, Kunsang C. Lama, Kyle A. Macleod, Shannon A. Miller, Megan Moschetti, Amanda Munoz, Jennifer O'Connell, Erin O'Neill, Emily A. Riley, Alejandro C. Rojas, Ryan T. Senecal, Delaney A. Smith, Nicholas J. Sousa, Karolyne N. Stimpson, Sabrina Vieira, Mckenzie R. Wood

BIO 255 Conservation Biology

The Salve Regina University Arboretum, located in Newport, Rhode Island is currently registered as a Level II arboretum and is intertwined with the city of Newport Arboretum. The university now has intentions to reach Level III status, as part of a ten-year plan. This plan was developed by the students of the Spring 2018 BIO 255: Conservation Biology course, instructed by Dr. Jameson Chace, Associate Professor of biology at Salve Regina University. As part of a curriculum geared towards civic engagement, the class focused on creating and optimizing strategies that can be applied to the ten-year plan. These strategies were …


Newall Glacier Nucleic Acid Analysis, Shannon Turner Apr 2018

Newall Glacier Nucleic Acid Analysis, Shannon Turner

Honors Projects

The Newall Glacier is located in Antarctica between Mount Newall and Mount Weyant, at approximately 77°30′S, 162°50′E. Having existed for millions of years, and being rarely touched by human populations, glaciers are a major source of information on climate and life in the past. During the past 5 decades, a multi-country team of scientists have collaborated to drill into many of Antarctica’s glaciers and ice fields, removing ice cores for scientific investigation. The ice core section chosen for this project was drilled from the Newall Glacier in 1988 and its depth was from 100.670 to 101.000 m. The purpose of …


Evaluating Effects Of Gene Mutations And Light Intensity On Arabidopsis Thaliana Development, Carolanne Bekus Apr 2018

Evaluating Effects Of Gene Mutations And Light Intensity On Arabidopsis Thaliana Development, Carolanne Bekus

Undergraduate Theses and Capstone Projects

Arabidopsis thaliana is a model organism often compared to commercial crops. The completion of sequencing A. thaliana’s genome has led to the next crucial challenge of determining gene function in these plants. The discovery of gene function within these plants will provide insights on how gene function can affect commercial crop production. This work compared wild-type Columbia (Col-O) A. thaliana to single gene mutants VPI/ABI3-like 1 (VAL1) and basic region/leucine zipper motif (bZIP). These single gene mutations may affect several traits that, in turn, can result in morphological changes and/or time of development in seedlings. Wild-type and …


Plants, Society, And The Environment, Thomas Harnden, Katie Bridges Apr 2018

Plants, Society, And The Environment, Thomas Harnden, Katie Bridges

Biological Sciences Grants Collections

This Grants Collection for Plants, Society, and the Environment was created under a Round Six ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

  • Linked Syllabus
  • Initial Proposal
  • Final Report


The Critically Endangered Forest Owlet Heteroglaux Blewitti Is Nested Within The Currently Recognized Athene Clade: A Century-Old Debate Addressed, Pankaj Koparde, Prachi Mehta, Sushma Reddy, Uma Ramakrishnan, Shomita Mukherjee, V. V. Robin Feb 2018

The Critically Endangered Forest Owlet Heteroglaux Blewitti Is Nested Within The Currently Recognized Athene Clade: A Century-Old Debate Addressed, Pankaj Koparde, Prachi Mehta, Sushma Reddy, Uma Ramakrishnan, Shomita Mukherjee, V. V. Robin

Biology: Faculty Publications and Other Works

Range-restricted species generally have specific niche requirements and may often have unique evolutionary histories. Unfortunately, many of these species severely lack basic research, resulting in poor conservation strategies. The phylogenetic relationship of the Critically Endangered Forest Owlet Heteroglaux blewitti has been the subject of a century-old debate. The current classifications based on non-phylogenetic comparisons of morphology place the small owls of Asia into three genera, namely, Athene, Glaucidium, and Heteroglaux. Based on morphological and anatomical data, H. blewitti has been alternatively hypothesized to belong within Athene, Glaucidium, or its own monotypic genus Heteroglaux. …


Biomimetic Macromolecules For Macrophage Targeting And Modulation, Joshua Whited Jan 2018

Biomimetic Macromolecules For Macrophage Targeting And Modulation, Joshua Whited

ETD Archive

Carbohydrate recognition has come to the forefront of biological aiming to uncover the mechanisms of physiological and pathological processes. Cell surface glycans are involved in processes including cellular adhesion, cell signaling, and immune response. A new approach for profiling cell surface glycans has great potential for a wide range of biomedical applications. Lectins have been conventionally used to determine the structure and function of glycoproteins, however, their numbers are still restricted compared to the number of glycan structures. Boronic acid has proven a remarkable small molecule capable of binding diols in aqueous solution. This interaction indicates boronic acid derived molecules …


Monitoring Ohio Bat Communities And Populations Using Mobile Acoustics, Molly C. Simonis Jan 2018

Monitoring Ohio Bat Communities And Populations Using Mobile Acoustics, Molly C. Simonis

Browse all Theses and Dissertations

The goal of my thesis is to: 1) provide baseline information of where Ohio bats are foraging in Wright State University's (WSU) campus woods in relation to forest age and habitat (Chapter 1), 2) determine potential roost availability for local bats (Chapter 1), and 3) examine changes in state-wide species composition following the introduction of White-nose Syndrome (WNS; Chapter 2). In Chapter 1, I created walking bat acoustic routes and used generalized linear models to determine what forest ages and habitats had the greatest bat activity in the WSU campus woods. I conducted habitat transects throughout all forest ages to …


Low-Impact Yoga Improves Flexibility, But Has No Effect On Heart Rate Variability In Sedentary Adult Women, Lauren Marie Shafer Jan 2018

Low-Impact Yoga Improves Flexibility, But Has No Effect On Heart Rate Variability In Sedentary Adult Women, Lauren Marie Shafer

Browse all Theses and Dissertations

Heart disease is the leading cause of death among adults in the United States and more than 600,000 people per year die when the condition goes untreated. Many cardiovascular maladies, such as high blood pressure and heart disease, can be markedly improved with lifestyle changes, including eating a healthy diet and regular exercise. In this study, 15 sedentary adult women (aged 19-63 years) participated in a prescribed 12-week yoga program. Electrocardiography was used to measure Heart Rate Variability, a tool that assesses autonomic tone on the heart. Autonomic nervous system activity is assessed at VLF, LF, and HF spectral components. …


Lifelines Winter 2018, Southern Adventist University Jan 2018

Lifelines Winter 2018, Southern Adventist University

Lifelines - Biology Department Newsletter

The Winter 2018 issue of Lifelines features articles on student missions in Peru, an alumni spotlight, and a pictorial directory of the 2018 biology and allied health graduates.


A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr. Jan 2018

A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr.

ETD Archive

Star polymers are a class of branched polymers comprised of several polymer chains extending from a central point. Star polymers have applications in biopharmaceuticals where they have been proposed to be suitable drug delivery vehicles. Star polymers have traditionally been synthesized through chemical synthesis with added functionality provided by grafting on the arms. This complex synthesis can be simplified by using a biosynthetic approach which enables precise control of molecular weight and composition. This approach is demonstrated using star polymers with arms composed of a temperature responsive protein-based polymer termed elastin-like polypeptide (ELP). Star polymers are characterized based on the …


The Naked Mole Rat Possesses A Differently Phased Core Clock System Along With A Different Glucose Handling And Mtor Systems Compared To The Common Lab Mouse, Soumyaditya Ghosh Jan 2018

The Naked Mole Rat Possesses A Differently Phased Core Clock System Along With A Different Glucose Handling And Mtor Systems Compared To The Common Lab Mouse, Soumyaditya Ghosh

ETD Archive

INTRODUCTION The Naked Mole Rat [ Heterocephalus glaber] is a type of rodent -with the highest average lifespan-30 years-among all the rodent species. It lives underground in sealed burrow systems with little to no exposure to day-night transitions on the surface. It shows polyphasic round the clock activity within its subterranean burrow system. The activity and physiology of most animals are governed by the biological circadian clock. The biological circadian clock is a system that oscillates with a rough periodicity of 24 hours. Environmental zeitgebers regulate the entrainment of the circadian clock to the 24-hour day-night cycle and light is …


A Comparison Of Two Methods Of Quantifying Mating Success In Low Density Gypsy Moth (Lymantria Dispar) Populations, Alexandra Barry, Hannah Byrne, Derek M. Johnson Jan 2018

A Comparison Of Two Methods Of Quantifying Mating Success In Low Density Gypsy Moth (Lymantria Dispar) Populations, Alexandra Barry, Hannah Byrne, Derek M. Johnson

UROP Posters

The gypsy moth (Lymantria dispar) is a defoliating pest native to Europe and invasive to North America. The gypsy moth is subject to depressed mating success in low density populations, which may restrict spread of the forest pest. Research focusing on gypsy moth density as it relates to mating behavior has often used counts of males caught in pheromone-baited delta traps as a proxy to estimate the probability of female mating success. The purpose of this project was to determine whether pheromone trap counts provide accurate estimates of female mating success probability, by comparing data gathered from pheromone-baited …


Neuromuscular Control Of The Calling Apparatus In The Túngara Frog (Engystomops Pustulosus), Kiran Kaur Grewal Jan 2018

Neuromuscular Control Of The Calling Apparatus In The Túngara Frog (Engystomops Pustulosus), Kiran Kaur Grewal

University of the Pacific Theses and Dissertations

Male túngara frogs can add a distinctive note ("chuck”) to their mating call. Production of the chuck involves vibrating a pair of laryngeal fibrous masses that is attached to the vocal cords. The muscular control of this mechanism remains unknown. Recent studies revealed a split in the laryngeal dilator muscle, which unveiled the deep dilator as a novel laryngeal muscle with unique attachments, innervation, and (likely) function. The deep dilator may position the fibrous masses for chuck production. The goals of this study were 1) to confirm the innervation of the novel muscle through electrophysiology; and 2) to determine the …


Noradrenergic Tuning, Not Simple Rate Effects, Produces Temperature-Sensitivity Of The Respiratory Network In Bullfrogs, Mauricio Vallejo Jan 2018

Noradrenergic Tuning, Not Simple Rate Effects, Produces Temperature-Sensitivity Of The Respiratory Network In Bullfrogs, Mauricio Vallejo

Browse all Theses and Dissertations

Animals match ventilation to metabolic and acid-base regulatory demands during changes in body temperature. Across vertebrates ventilation increases at warmer temperatures and decreases at cooler temperatures. At the organismal level this is attributed to metabolic feedback and/or alpha-stat pH regulation; however, the cellular mechanisms that produce ventilatory output in response to brain temperature changes remain unclear. To identify mechanisms underlying temperature-sensitivity of the respiratory control network, I used brainstem-spinal cord preparations producing spontaneously active, rhythmic motor output similar to breathing in vivo of adult bullfrogs Lithobates catesbeianus. In vitro brainstem-spinal cords were superfused with artificial cerebrospinal fluid (aCSF) equilibrated at …


Characterization Of The Effect Of Optineurin On Alpha-Synuclein Aggregation And Toxicity In Yeast, Md Moydul Islam Jan 2018

Characterization Of The Effect Of Optineurin On Alpha-Synuclein Aggregation And Toxicity In Yeast, Md Moydul Islam

Browse all Theses and Dissertations

Optineurin, an autophagy adaptor protein genetically linked to Normal Tension Glaucoma and Amyotrophic Lateral Sclerosis, has been found in the pathological inclusions of various other neurodegenerative disorders, supporting an important role of optineurin in neurodegeneration. Using yeast as a model, we found that overexpression of optineurin drastically enhances the toxicity of the Parkinson's disease-causing protein, alpha-synuclein. Considering the conserved protein-protein interaction between optineurin and Ypt1, a yeast suppressor of the toxicity of both optineurin and alpha-synuclein, we hypothesize that cellular targets of optineurin underlie in the cytotoxicity and the enhancer effect. Using genome-wide yeast two-hybrid screens, we identified 97 yeast …


Zero Textbook Cost Syllabus For Bio 3005 (Molecular And Cellular Biology), Krista Dobi, Kim Macklin Jan 2018

Zero Textbook Cost Syllabus For Bio 3005 (Molecular And Cellular Biology), Krista Dobi, Kim Macklin

Open Educational Resources

The biology of cells is examined with an emphasis on the relationship between organelle structure and function. Activity of the nucleus, cell structure, division and growth, and tools for studying genes will be discussed. Laboratory experiments are performed with isolated organelles or intact cells. Techniques include cell fractionation, bio-chemical assays, and DNA isolation and modification. Students will also read and analyze articles from scientific journals.


Zero Textbook Cost Syllabus For Env 3009/Bio 4009 (Conservation Biology And Sustainable Development), Natalia Borrego Jan 2018

Zero Textbook Cost Syllabus For Env 3009/Bio 4009 (Conservation Biology And Sustainable Development), Natalia Borrego

Open Educational Resources

Conservation biology is an interdisciplinary topic that explores how we can protect and maintain natural areas. Due to the resources we take and impacts we have on natural environments, this field is directly related to restoration ecology (restoring natural areas) and sustainable development/natural resource management. We will explore the basis for these related fields from an ecological, social, legal, and cultural perspective, as all conservation and management projects take place in the larger human landscape. We will consider how we measure biodiversity, why it matters, why is it is threatened, and how we can manage (protect, restore, maintain, use) it …


Full Issue: Volume 11, Number 2 Jan 2018

Full Issue: Volume 11, Number 2

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


The Effect Of Increased Quizzing On Retention Of Material By Histology Laboratory Students, R. J. Nogrady Jan 2018

The Effect Of Increased Quizzing On Retention Of Material By Histology Laboratory Students, R. J. Nogrady

Browse all Theses and Dissertations

In traditional approaches to teaching, examinations and quizzes have been considered secondary activities, designed to assess and motivate learning, but not generally as teaching tools in themselves (Roediger and Butler, 2011). However, abundant psychological research in laboratory settings indicates that the act of taking a quiz or examination on the material can directly enhance retention of that material in ways which are distinct from and often more effective than restudying of the material. This phenomenon is now referred to as the testing effect. The testing effect hypothesis asserts that (1) repeated retrieval attempts have a longer lasting effect on retention …


Lonicera Maackii Alters Decay Dynamics Of Coarse Woody Debris, Michaela J. Woods Jan 2018

Lonicera Maackii Alters Decay Dynamics Of Coarse Woody Debris, Michaela J. Woods

Browse all Theses and Dissertations

Since industrialization, anthropogenic carbon emissions have led to excess atmospheric carbon dioxide that may alter the stability of ecosystem processes. Microorganisms are essential in mitigating excess carbon and play a notable role in the breakdown of organic material. This process, decomposition, is essential in forested ecosystems where microorganisms can recycle nutrients and store carbon in soil organic matter or release it through respiration. Fungi participate in decomposition through the release of enzymes responsible for carrying out the chemical reactions that break down plant material. Species introductions have the potential to alter decomposition dynamics. In the Midwestern US, the invasive shrub …


Biol 448-H01: Neuropathophysiology, Darshan Desai Jan 2018

Biol 448-H01: Neuropathophysiology, Darshan Desai

Biology Syllabi

No abstract provided.


Building Capacity For A Global Genome Editing Observatory: Conceptual Challenges, J. Benjamin Hurlbut, Sheila Jasanoff, Krishanu Saha, Aziza Ahmed, Anthony Appiah, Elizabeth Bartholet, Francoise Baylis, Gaymon Bennett, George Church, I. Glenn Cohen, George Daley, Kevin Finneran, William Hurlbut, Rudolf Jaenisch, Laurence Lwoff, John Paul Kimes, Peter Mills, Jacob Moses, Buhm Soon Park, Erik Parens, Rachel Salzman, Abha Saxena, Hilton Simmet, Tania Simoncelli, O. Carter Snead, Kaushik Sunder Rajan, Robert D. Truog, Patricia Williams, Christiane Woopen Jan 2018

Building Capacity For A Global Genome Editing Observatory: Conceptual Challenges, J. Benjamin Hurlbut, Sheila Jasanoff, Krishanu Saha, Aziza Ahmed, Anthony Appiah, Elizabeth Bartholet, Francoise Baylis, Gaymon Bennett, George Church, I. Glenn Cohen, George Daley, Kevin Finneran, William Hurlbut, Rudolf Jaenisch, Laurence Lwoff, John Paul Kimes, Peter Mills, Jacob Moses, Buhm Soon Park, Erik Parens, Rachel Salzman, Abha Saxena, Hilton Simmet, Tania Simoncelli, O. Carter Snead, Kaushik Sunder Rajan, Robert D. Truog, Patricia Williams, Christiane Woopen

Journal Articles

A new infrastructure is urgently needed at the global level to facilitate exchange on key issues concerning genome editing. We advocate the establishment of a global observatory to serve as a center for international, interdisciplinary, and cosmopolitan reflection.


Full Issue: Volume 12, Number 1 Jan 2018

Full Issue: Volume 12, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


The Effects Of Aqueous Nitrate On Freshwater Crayfish, Erik Hartman Jan 2018

The Effects Of Aqueous Nitrate On Freshwater Crayfish, Erik Hartman

Williams Honors College, Honors Research Projects

Globalization and a rising need for greater production from the agricultural system have increased the use of fertilizer by farms across the entire country. The purpose of this experiment was to observe the effects of aqueous nitrate (commonly found in many fertilizers) on the metabolic rate and hemolymph lactate concentration of freshwater crayfish. After exposure, there was no observed change in metabolic rate, but there was a significant decrease in hemolymph lactate concentration in the groups exposed to nitrate.


Osmotic Activation Of Sperm Motility Via Water Flow Through Aquaporins In The Freeze-Tolerant Cope's Gray Treefrog, Dryophytes Chrysoscelis, Deja Miller Jan 2018

Osmotic Activation Of Sperm Motility Via Water Flow Through Aquaporins In The Freeze-Tolerant Cope's Gray Treefrog, Dryophytes Chrysoscelis, Deja Miller

Browse all Theses and Dissertations

Gametes of gray treefrogs, Dryophytes chrysoscelis, are deposited into freshwater ponds. Sperm undergo spermatogenesis and maturation beginning in the seminiferous tubules and migrating to the lumen. In mammals and fishes, these cells are immotile within the isosmotic fluid of the testes and have motility activated by exposure to a hyper- or hypoosmotic medium. Water flows into or out of the sperm cell, altering intracellular ionic concentrations, and ultimately stimulates flagellar movement. We tested the hypothesis that exposure to a hypotonic environment activates motility of gray treefrog sperm. We also hypothesized that osmotic water uptake is facilitated by expression of water …


Nocturnally-Migrating Birds Traverse Earth's Most Light-Polluted Regions, And Bright Lights Confound Their Habitat Use En Route, Jeffrey J. Butler, James D. Mclaren, Sergio A. Cabrera-Cruz, Jaclyn A. Smolinsky, Timothy D. Schreckengost, Matthew E. Boone, E. Emiel Van Loon, Deanna K. Dawson, Eric L. Walters Jan 2018

Nocturnally-Migrating Birds Traverse Earth's Most Light-Polluted Regions, And Bright Lights Confound Their Habitat Use En Route, Jeffrey J. Butler, James D. Mclaren, Sergio A. Cabrera-Cruz, Jaclyn A. Smolinsky, Timothy D. Schreckengost, Matthew E. Boone, E. Emiel Van Loon, Deanna K. Dawson, Eric L. Walters

Biological Sciences Faculty Publications

No abstract provided.


Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister Jan 2018

Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is applied to tributaries of the Great Lakes to control invasive sea lampreys (Petromyzon marinus). Although TFM is selectively toxic to larval sea lampreys, non-target mortality can occur during lampricide treatments. It is important to know whether or not TFM played a role in the death of these fishes, and the most direct means to do this is using forensic science principles. The objectives of this study were to: (i) determine the acute toxicity of TFM to the non-target fishes, rainbow trout (Oncorhynchus mykiss) and white sucker (Catostomus commersonii), and how the lampricide is …


Crispr Genetic Editing: Paths For Christian Acceptance And Analysis Of In Vivo And In Vitro Efficiency, Mandeep Sandhu Jan 2018

Crispr Genetic Editing: Paths For Christian Acceptance And Analysis Of In Vivo And In Vitro Efficiency, Mandeep Sandhu

Scripps Senior Theses

With advancements in CRISPR-cas9 broadening the potential paths for clinical usage of genetic editing, conversations about genetic editing have grown to outside simply scientific communities and into mainstream conversations. This study focuses specifically on Christian discourse of genetic editing and locates four major tensions for many Christians when they think about genetic editing: beginning of life, Creator-human relationship, imago Dei, and stewardship. With these major concerns in mind, I identify epigenetics, somatic cell genetic editing, and in vivo genetic editing research as important research paths to pursue as they can potentially produce techniques that more Christian individuals would feel comfortable …


Endocrine Responses To Repeated Adrenocorticotropic Hormone Administration In Free-Ranging Elephant, Molly Mccormley Jan 2018

Endocrine Responses To Repeated Adrenocorticotropic Hormone Administration In Free-Ranging Elephant, Molly Mccormley

University of the Pacific Theses and Dissertations

Understanding the physiological response of marine mammals to anthropogenic stressors can inform marine ecosystem conservation strategies. Stress stimulates release of glucocorticoid (GC) hormones, which increase energy substrate availability while suppressing energy-intensive processes. Exposure to repeated stressors can potentially affect an animal’s ability to respond to and recover from subsequent challenges. To assess the endocrine response of a marine mammal to repeated stressors, we administered adrenocorticotropic hormone (ACTH) to free-ranging juvenile northern elephant seals (Mirounga angustirostris; n=7) once daily for four days. ACTH administration induced significant, but transient (<24 h) elevation in circulating cortisol levels (p < 0.0001). These increases did not vary in magnitude between the first ACTH challenge on day 1 and the last challenge on day 4. In contrast, aldosterone levels remained elevated above baseline for at least 24 hours after each ACTH injection (p < 0.001), and responses were greater on day 4 than day 1 (p < 0.01). Total triiodothyronine (tT3) levels were decreased on day 4 relative to day 1 (p < 0.01), while reverse triiodothyronine (rT3) concentrations increased relative to baseline on days 1 and 4 (p < 0.001) in response to ACTH, indicating a suppression of thyroid hormone secretion. There was no effect of ACTH on the sex steroid dehydroepiandrosterone (DHEA). These results suggest that elephant seals are able to mount adrenal responses to multiple ACTH challenges. However, repeated stress results in facilitation of aldosterone secretion and suppression of tT3, which may impact osmoregulation and metabolism. We propose that aldosterone and tT3 are informative additional indicators of repeated stress in marine mammals.